SEOUL -- Korean Air, the top flag carrier in South Korea, recommended teleworking for pregnant women and other employees working at non-face-to-face worksites after a 24-year-old female flight attendant was infected with a highly contagious new coronavirus following her overseas duty covering Los Angeles and Tel Aviv.

A Korean Air flight attendant tested positive for the virus on Tuesday while staying at her home for self-quarantine, according to the Korea Centers for Disease Control and Prevention (KCDC). She showed symptoms during her shuttle flight on the Incheon-Los Angeles route from February 19 to 22.

She had been assigned to the Incheon-Tel Aviv route aboard the same plane used by churchgoers who returned home on February 16 after a trip to Israel. The Roman Catholic Church in South Korea has taken a series of steps to prevent secondary infections after 29 followers tested positive for the coronavirus after a pilgrimage to Israel.

Korean Air did not say how many flight attendants were placed into obligatory self-quarantine for two weeks. On Wednesday, the company disinfected facilities used by flight attendants and recommend telecommuting for pregnant women and other employees who are not involved in face-to-face work with clients and quests.

KCDC director Jeong Eun-kyeong said that an epidemiological survey is under way to see if the flight attendant was infected as a result of exposure to contaminated air in the cabin or in other areas. "We're working on a final check of the infection route," she told a regular press briefing on Wednesday.

Theoretically, air in the cabin of commercial airplanes is safe as the air pressure does not allow humans to breathe independently. Hot compressed air is drawn from the engines and, once cooled, directed into the cabin to supply breathable air, known as bleed air. Recycled air in the cabin is combined with outside air compressed by the aircraft's engines.